An orthopaedic surgical instrument designed to open and enlarge the medullary canal (e.g., in the femur, tibia, ulnar) for the insertion of various devices during prosthesis implantation or fracture fixation procedures. It is typically designed as a long, cylindrical, rigid shaft with straight, spiralled, or contoured flutes that function as cutting surfaces; it may include a transverse milling (spotfacing) burr to level the end of the bone (e.g., post amputation). It is typically made of a high-grade stainless steel and is available in various sizes. It is intended for manual or powered rotation. This is a reusable device intended to be sterilized prior to use.